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Chapter 11-Water
Water Resources
Water
“Water Planet”- Earth has an abundance of
water in all forms: solid, liquid, and gas.
Renewable resource because it is circulated in
the water cycle.
Humans can only survive a few days without
water.
Two kinds of water on Earth:
Fresh water- Can drink because it contains little salt.
Salt water- Ocean water with a high concentration of
salt.
The Water Cycle
Global Water Distribution
97% salt water
3% fresh water
77% of fresh water
frozen in icecaps and
glaciers
22% ground water
1 % other
Global Water Distribution
Surface water- Fresh water on Earth’s
land surface.
Lakes, rivers, streams, and wetlands
River systems- Flowing network of water
comprised of streams and rivers.
Amazon river system- largest in the world
Watershed- Area of land that is drained by a
river.
Watersheds of the World
Global water Distribution
Ground Water- Water stored beneath the
Earth’s surface in sediment and rock
formations.
Water table- Level where the rocks and soil are
saturated with water
Aquifer- Underground formation that contains
water
Porosity- Amount of space between the particles
that make up a rock.
Permeability- The ability of rock or soil to allow
water to flow through it.
Permeable- Allows the flow of water.
Impermeable- Does not allow the flow of water.
Ground Water- Cont’d.
The Recharge Zone- The area of the
Earth’s surface where water percolates
down into an aquifer.
Wells- A hole that is dug or drilled to
reach groundwater
Chapter 11-Water
Water Use and Management
Global Water Use
Most freshwater used
globally to water
crops.
19% of global water
use for industry
Only 8% of global
water used for
washing and
drinking.
Residential Water Use
Striking differences
among countries
around the world
U.S. residents use on
average 300 L of
water per day
Indian residents use
on average 41 L of
water per day
Water Treatment
Potable- Safe to drink.
Treatment must remove elements:
mercury, arsenic, and lead
Found in polluted and ground water
Pathogens- Organisms that cause illness
or disease
See Figure 6, Pages 276-277
Water Treatment
Water Use
Industrial- 19% of
water use in world
Manufacture goods
Dispose of waste
Generate power
Most used to cool
power plants
Agricultural- 67% of
water use in world
80% of water used in
agriculture
evaporates
Irrigation- Method of
providing plants with
water from sources
other than direct
precipitation.
Water Use
Water Management Projects
Aqueducts- Huge canals that brought water
from the mountains to dry areas.
Dams and water diversion canals used today.
Water management projects today:
Bring in water to make a dry area habitable
Create a reservoir for recreation or drinking water
Generate electric power
Water Management Projects
Water Diversion Projects- To supply dry
regions with water, all or part of a river
can be diverted into canals that carry
water across great distances.
Water Management Projects
Dam- Structure built across a river to
control the river’s flow.
Can be used to generate electricity.
Problems: flooding, ecosystem destruction,
and dam failure
Fertile sediment builds up behind dams
Reservoir- Artificial lake formed behind a
dam.
Water Conservation
Water becomes more expensive as it
depletes.
Agriculture: Most water loss from
evaporation, seepage, and runoff
Drip Irrigation System- Small amounts of
water delivered directly to roots using
perforated tubing.
Water Conservation
Home:
Water-saving technology such as low-flow toilets
and shower heads
Water lawns at night
Xeriscaping- Designing landscapes that require
minimal water use.
Industry:
Recycling of cooling water and wastewater
City wide/company wide water saving plans
Solutions for the Future
Desalination- Process of removing salt from
salt water
Heats water and collects evaporation
Middle East/Kuwait has desalination plants
Transporting Water
Transporting in bags and/or large plastic containers
from abundant supplies to low supplied regions
Towing icebergs??
Chapter 11-Water
Water Pollution
Water Pollution
The introduction of chemical, physical, or
biological agents into water that degrade
water quality and adversely affect the
organisms that depend on the water.
Types of Water Pollution
 Nonpoint-source
Pollution
 Pollution that comes from
many different sourecs
 Difficult to identify and
trace/regulate and control
 96% of polluted water in
U.S
 Point-source Pollution
 Pollution discharged from
a single source
 Can be identified and
traced
.
Pollutant Types and Sources
Wastewater
Water that contains waste from homes or
industry.
Treating
Most contaminates are biodegradable
Some toxic substances cannot be removed by
standard treatment
Wastewater
Sewage sludge
Solid material that remains after treatment
Sometimes hazardous waste
Often incinerated and ash buried
Can be used as fertilizer or bricks
Water Pollution
Eutrophication
Containing an
abundance of
nutrients
Leads to swamp or
marsh
Artificial
EutrophicationSewage and fertilizer
runoff enhances
Ex: Algal blooms
Thermal PollutionIncreased
temperature of water
sources caused by
factories and
industries cooling
systems
Decreases oxygen
levels
Kills organisms
Water Pollution
Groundwater
pollution- Polluted
surface water
percolates down to
groundwater
Leaking underground
storage tanks are
large problem
Remains for 100s to
1000s of years
Ocean pollution
Coastal ecosystems
most affected
Legal to dump in
some parts of ocean
Oil spills
5% of ocean pollution
Nonpoint-source
pollution from land 10
times more than
tanker spills
Oil Spills
Water Pollution
BiomagnificationAccumulation of
pollutants at
successive levels of
the food chain.
Many pesticides
Example: DDT and
the Bald Eagle
 Clean Water Act of
1972- To restore and
maintain the chemical,
physical, and biological
integrity of the nation’s
waters.
 Goal to make fishing and
swimming safe by 1983.
 Not achieved
 30% increase
 Opened door for more
legislation
Biomagnification
Water Quality Federal Laws